Thanks. Yes, the files are OK. Thousands KB of all the files mean Hundreds of MBs, which you see i.e. 241 MB.
My advice is not to delete stuff inside OS folders, doing so may put Windows in a bad state. Do it on your own risk.
Microsoft Defender
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Anonymous
Can I delete files in backup folder in definition updates in Microsoft defender?
Windows for home | Windows 11 | Files, folders, and storage
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
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Anonymous
2022-05-17T10:36:11+00:00 Mine is 241mb in backup folder. And the files inside backup folder is thousands kb. It's too much.
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Sumit D - IA 170.7K Reputation points Independent Advisor2022-05-17T05:01:41+00:00 It is a mere 230 MB for me. What size is in yours?
I would recommend not to delete anything in system folders.
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Anonymous
2022-05-17T03:45:33+00:00 The backup folder is in definition update folder in Microsoft defender folder.
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Sumit D - IA 170.7K Reputation points Independent Advisor
2022-05-17T01:42:49+00:00 Hi Emily,
I am Sumit here to assist you with this question.What is the path of the backup folder in question?